* Add aggregate for junos modules and sub spec validation
* aggregate support of junos modules
* aggregate sub spec validation
* relevant changes to junos integration test
* junos module boilerplate changes
* Add new boilerplate for junos modules
* Fix CI issues
* Add junos_banner declartive module
* junos_banner implementation
* Integration test for junos_banner
* Integration test for net_banner (junos)
* Minor fixes
* Minor doc change